Why do we have leap years, and how do they keep calendars aligned?

We add an extra day every few years to keep our calendar matching up with the year, which is how long it takes Earth to go around the Sun.

Imagine you and your friend are playing a game where you take turns counting. Every time you finish one full circle around the room, that’s like one year. But if you always count 365 steps every time, you’ll slowly drift out of sync with your friend, just like our calendar drifting out of sync with the real year.

That’s why we have a special day called leap day, which is on February 29th. We add it every 4 years to catch up. It's like giving your calendar an extra step so it can keep up with Earth’s journey around the Sun.

If we didn’t add that extra day, after a few years, our calendar would be off by one day, meaning February would come before January! That might sound silly, but over time, it could mess up holidays and events. So leap years are like a little boost for the calendar to stay in rhythm with Earth’s path around the Sun.